reptiles and birds have a common , and are therefore placed in the same clade.

reptiles and birds have a common , and are therefore placed in the same clade.

reptiles and birds have a common , and are therefore placed in the same clade.

Answer

Brief Explanations:

In taxonomy, organisms in the same clade share a common ancestor. Reptiles and birds are grouped together in a clade because they share a common evolutionary origin.

Answer:

ancestor